tire pressure

[staedtler]

guys... for any of you running Michelin Pilot Sports (or power)...

can anyone remind me of the tire pressure?...

I think is 34 front, 32 back for the street? (or is it the other way?)

 

just checking...i can't freak'n remember

[Guest trispeed]

almost all tire manufacturers recommend 34-36 ft and 38-40 rear for the street. Go to 32 ft and rear for a track day.

The bike doesn't seem to matter, whether it weighs 400 or 550.

[docc]

Right, 33 ft, 37 rr. I've been running the rear up to 39 for fast highway runs but trust the 33 psi front to stick better than higher pressures.

[staedtler]

[Baldini]

almost all tire manufacturers recommend 34-36 ft and 38-40 rear for the street. ....

 

s'too much air. think who might be going without - you yanks gotta realise we all gotta share our planet. 31-33 f, 36-38 rear is enough air for any one man......

 

KB

[Guest trispeed]

my new Continental Road attack rear tire came with a sticker (decal) on it stating 'minimum 42psi cold'.

maybe they just don't know what they're talking about.

why do so many riders think that a little shade tree mechanics outpace millions of dollars spent on professional R&D?

There's a question for the ages.

[DeBenGuzzi]

my new Continental Road attack rear tire came with a sticker (decal) on it stating 'minimum 42psi cold'.

maybe they just don't know what they're talking about.

why do so many riders think that a  little shade tree mechanics outpace millions of dollars spent on professional R&D?

There's a question for the ages.

81263[/snapback]

Just because they spent a lot of money doesn't mean they know what they are doing

Although, I'll give them most of the time.

[Guest trispeed]

that's a beautiful ride, or are you being sarcastic.

If people would spend more time learning how to ride and less time blaming the bike, you would all have a lot more fun. The tire companies know more about tires than you or I or the next guy who spends the occasional weekend riding a bike. Let's get serious for minute and be honest with ourselves. The biggest variable is always the RIDER.

I've heard it all; when I pass Ducati guys round the outside at a track day on my Goldwing Aspencade, they can't blame the bike then. That's quite satisfying for me, I'll tell 'ya.

[Ouiji Veck]

Conti road attacks call for higher PSI for whatever reason...

I was running mine @ 40...compromiseing..

They were holding up well....but then I got a sick valve...who knows

how many milesI ran it low one of the last times I was out......Dammm!

The never ending struggle for tire life and performance goes on.....and on..........

[Guest trispeed]

this is what I mean, what do you feel you are compromising, your safety, performance, tread life? Why compromise at all; just run it at the spec the manufacturer advises.

[Guest ratchethack]

I'm more'n open to learn a few things here about tire pressure, as I'm certainly no expert, and I reckon many 'round here might well know lots more about tires than I do!!

 

It seems to me that tire mfgr's make recommendations on pressures based on assumptions that take into consideration a wide range of the most common riding factors under which a tire will most likely be used. Then they come up with something that they believe will be a COMPROMISE NUMBER (or a small range) for pressure that's most likely to be the safest pressure for the largest number of riders under the widest ranges of likely conditions and uses.

 

It's sorta like coming up with a design for a seat or spec-ing out a set of springs... You have to put SOMETHING on the bike that won't cause it to be a negative buying factor on the dealer floor for the greatest number of potential buyers, and at the same time have something that at least works well enough for the widest range of riders under the widest range of uses and applications that the bike is likely to be ridden. Sorta like "off the rack" measurements that the tailor starts with to custom-fit a set of leathers or a suit...

 

A market-based compromise pretty much guarantees that what the mfgr. comes up with isn't going to be exactly right for a very large number of riders - but it attempts to be NOT TOO FAR OFF what a large number of riders need on a given ride, either. It more'n likely gets calculated on a "bell distribution curve". But if your weight, for example, or your riding conditions (or both) put you somewhere outside of that big lump on the bell curve, y'er simply not gonna achieve a very good "fit" - whether it be with spring rates, seat, or recommended tire pressures, depending on how you ride. I b'lieve many beginning riders (in particular) mistakenly don't give any of this a thought. They assume it's like a car - You hardly ever consider load, temperature or road conditions for tire pressures in a car - ya occasionally checks y'er tire pressures and ya drive away in confidence without giving a thought to the suspension at all...but IMHO this thinking ain't actually ever applicable (or even very safe ) with motorcycles...

 

Who cares, and why all the fuss?! Well, I'm glad I do... I ain't unintentionally parted company with even one of a dozen bikes I've owned yet (on the road, anyway) in probably hundreds of thousands of miles and I plan to keep it that way. I've seen first-hand what negligence of this stuff can do, and there's been at least one example of this that I know of on this Forum - and it weren't none too pretty.

 

I figure motorcycles ain't at all like cars, in the sense that to achieve performance for which they're designed, they always require a far greater degree of tailored matching of chassis setup to their intended use - and that includes tires and tire pressure to my way of thinking.

 

Consider that a car may be 20-30X the weight of the driver. The bell curves on tire pressure and spring rates over a population of riders/drivers are a whole lot narrower for a motorcycle, which may only weigh only 2.5-3X what a rider weighs. Add a passenger to a typical car - the driver can't even detect a difference. Put a passenger on a bike, and suddenly it's a brand new world...So proportionately, the rider needs to pay LOTS more attention to tire pressures and suspension on the motorcycle than with a car - whether he's carrying a passenger, or even as much as 50 lbs. of his own weight and/or cargo that's over the compromised "norm" - if he wants to achieve something close to the performance of which the chassis is capable as designed.

 

Now In my case, (for the purposes of y'er garden variety Road Geez ), when I consider that what a tire mfgr. comes up with for a recommended pressure for a Sport/Touring tire takes into consideration a significant population of riders using the tire for 2-up riding with bags loaded (which in my case, I never do), ambient temperatures in "moderate" ranges (which I sometimes substantially exceed, especially in the summer), I try to use common sense and extrapolate my pressures using the recommended pressure as a guide.

 

Seems to me that second-guessing the recommended pressure by the mfg'r should be done sensibly, and only advisedly.

 

I always check 'em before a ride of any length. For a Sport/Touring tire, I usually whack at least 3-4 lbs off the recommended pressure for the rear for solo, no-cargo riding for starters, and adjust for temps and surface conditions I'm likely to encounter during the ride from there. I've done the rule-o'-thumb 1/10 hot/cold temp/pressure calculation many times (especially on hot days) and generally use this only as a guide also.

 

Following the above thinking has given me very good results on the road. Using this philosophy with my current choice of tires on the Guzzi (Metz Z6), to the best of my ability to determine the performance of the tires, they haven't anywhere near run out of performance before I run out of riding ability yet - under an amazing range of riding conditions, and I don't expect 'em to, either...but that's merely a Road Geez analysis.

 

My usual "starting point" is 34#F and 37#R for mountain riding with the Z6. And I LOVE these tires!

 

Comments?

 

BAA, TJM, & YMMV

[Guest trispeed]

Here it is again, why are we second guessing the manufacturers at all. What do we think they are conspiring to do that will affect the end user in a negative fashion??

The old method of looking for a 10% rise from cold to hot pressue is just that; the old method. Ask a tire rep at the track next time you're there. That applied to bias ply tires but not new radials.

The Dunlop tire expert said run 36/38-40 on the road and 31ft, 29-30 rear for a track day. Expert riders only, as the low pressure takes away straight line stability; you'll weave down the front straight but the extra grip ( only for a 20 minute session) is beneficial if you really know how to ride fast.

Does he know less than you or I? He's the guy with all the information.

Ride more, fiddle less.

[Ouiji Veck]

Ha!

I can't be retrained....

The first thing we used to do to our brand new..I mean ZERO miles..

MX bikes was rip the air box/ filter out and toss 'em...bring the main needle

up a click or 2....change the fork oil...cut the bars...

What i THINK I'm compromising is milage for traction...(ain't we all)

Yea...I believe the experts...but get two of 'em togeather and there's gonna be a fight!

I'm always fighting with my tire pressure....where does it go?

I get real antsy on a trip...loaded with luggage...the more I check it..the more it changes.

God I have a lot of fun though. Self deprecating humor goes a long way with me.

[Guest trispeed]

A fresh set of modern radials will give any street rider more than enough traction, at the prescribed pressure. The guys that think sliding a bit means they are riding as fast as can be are fooling themselves. They are riding poorly, one must ride with smooth, controlled inputs to be fast and safe.

I have personally witnessed a rider on a much superior bike, sliding BOTH ends and feeling that he's ringing out the bike for all its worth, only to be passed quite easily, by a rider on a 'beginner' bike; heavier with smaller tires, low technology everything and 40% less power. All this on the track, mind.

After I crashed trying to keep up with this guy, I decided to learn more about riding, with first hand knowledge that the superior equipment meant nothing.

It's 98% rider!!!

Fiddling with tire pressure and a mm of sag here and there is ignoring the primary issue. Learn to ride better, that's the key. I had a blast on my 2004 V11 Sport, all stock. I was able to blow by plenty of 'real' sport bikes and those guys were all thinking about why their bike wasn't fast enough. The V11 drew a small crowd after most of the sessions, with guys scratching their heads and wondering why this bike was so fast. Great for me that they still don't get it, I suppose.

[Ouiji Veck]

Yup. "It's 98% rider!!!"

You learn that the first few months of racing.

Imagine what you learn racing every week end for 10 yrs.

Mostly ya learn to quit trying to prove anything, just go out and have a good time

It's all for fun. (unless your getting paid )